Using an experimental DNA-based therapy, scientists might slow the self-destructive immune reaction against insulin-making cells that causes type 1 diabetes. The finding, appearing in the June 26 Science Translational Medicine, represents a promising but preliminary advance toward devising a treatment for the condition, which often strikes in childhood.

Lawrence Steinman of Stanford University and his colleagues injected 26 volunteers weekly with placebos. Another 54 got the experimental tr...